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A228478 Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

%I A228478 #12 Sep 11 2018 09:46:19
%S A228478 3,9,41,172,728,3084,13050,55252,233875,990055,4191028,17741339,
%T A228478 75101906,317918500,1345800258,5696989354,24116274286,102088075950,
%U A228478 432155280235,1829382955772,7744072911728,32781908823977,138771103836595
%N A228478 Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.
%C A228478 Same recurrences as A228285 except in addition a smaller one for column 5.
%H A228478 R. H. Hardin, <a href="/A228478/b228478.txt">Table of n, a(n) for n = 1..210</a>
%F A228478 a(n) = a(n-1) + 10*a(n-2) + 15*a(n-3) + 4*a(n-4) - 6*a(n-5) - a(n-6) + 3*a(n-7) - a(n-8).
%F A228478 Empirical g.f.: x*(3 + 6*x + 2*x^2 - 4*x^3 - x^4 + 3*x^5 - x^6) / (1 - x - 10*x^2 - 15*x^3 - 4*x^4 + 6*x^5 + x^6 - 3*x^7 + x^8). - _Colin Barker_, Sep 11 2018
%e A228478 Some solutions for n=4:
%e A228478 ..1..0..1..0....1..0..1..0....1..0..0..0....1..0..0..1....1..0..0..0
%e A228478 ..0..0..0..1....0..0..0..0....0..1..0..1....0..0..0..0....0..0..0..0
%e A228478 ..1..0..0..0....0..0..0..1....0..0..0..0....1..0..0..1....0..1..0..1
%e A228478 ..0..1..0..0....0..1..0..0....0..1..0..1....0..1..0..0....0..0..0..0
%Y A228478 Column 4 of A228482.
%K A228478 nonn
%O A228478 1,1
%A A228478 _R. H. Hardin_, Aug 22 2013